Lead + CA glue: a dangerous combination...

This is something brought to my attention by our friend Nei Biazetto. Although most of us have already heard about it, I for one have never seen the actual consequenses. I'm talking about the usual method of glueing weights inside models to avoid the well known tail-sitting problem. The most commom method to prevent it is to glue lead balls in hidden spots of our model to make its center of gravity remain between the landing gear legs. This makes the model to sit properly on the wheels, instead of laying back on its tail. P-38s, Moskitos and B-25s are prime examples...

Well, if you like to use white glue to cement the lead in your models, stop reading now and do yourself a favor: keep using white glue. If not, be aware that a very undesirable phenomenon will probably happen to your models (or already have - cross your fingers).

I don't know exactly what is the chemical reaction which takes place in the dark interior of our models, but it seems to form an ever growing layer of oxide (or salt?) visually similar to what happens to your car battery terminals: a white, brittle stuff... The fact is that the stuff doesn't stop growing, until it fills up the model cavity where the lead was glued, and increasing the internal pressure to the point of actually breaking your model apart.

Nei showed me a couple of models in his collection suffering from the problem. These are valuable examples. Look at the engine nacelle of this 1/72 Focke-Wulf Ta-154, it has broken along the seam line, the same happening to the fuselage (in spite of a previous Nei's attempt to correct the problem):

Nei told me that the process takes time. About 5-10 years in his cases. And it is an ugly view. This Heinkel He-219 literally exploded beyond repair:

And before you try to repair the crack, remember, the stuff will keep growing inside your model. Always use white glue or even better, avoid lead.

I recall reading somewhere a set of directions to be followed by professional ship modelers in order to have their models accepted by museums. That included a tacit "No lead parts" and even a "No paints with lead content". Now I know why...

I hope you find this tip useful. And if you have more information or photos on the subject, please drop me a line.

Rato Marczak © 2008